CA1233492A

CA1233492A - Apparatus for pumping fluent solid material

Info

Publication number: CA1233492A
Application number: CA000481014A
Authority: CA
Inventors: Avrom R. Handleman
Original assignee: Semi Bulk Systems Inc
Current assignee: Semi Bulk Systems Inc
Priority date: 1984-08-31
Filing date: 1985-05-08
Publication date: 1988-03-01
Also published as: DE3577465D1; EP0173639B1; DE173639T1; EP0173639A3; EP0173639A2; US4521165A

Abstract

ABSTRACT OF THE DISCLOSURE
Apparatus for pumping fluent solid material comprising first and second expansible chamber pumps and means interconnect-ing the pumps. The first expansible chamber pump has an inlet with a check valve for intake of material from a supply thereof on an intake stroke of the first pump and an outlet with a check valve for discharge of the material on a dischage stroke of the first pump. The apparatus also has a line for delivery of mate-rial from the outlet of the first pump, The second expansible chamber pump has an inlet with a check valve for intake of gas on an intake stroke of the second pump and an outlet with a check valve for discharge of gas on a discharge stroke of the second pump. Means interconnect the pumps for operation of the second pump through a discharge stroke on an intake stroke of the first pump and through an intake stroke on a discharge stroke of the first pump. A gas line interconnects the outlet of the second pump to the material delivery line downstream from and adjacent the outlet of the first pump whereby on each discharge stroke of the first pump the second pump takes in gas and on each intake stroke of the first pump the second pump pumps gas to the material delivery line behind the material delivered into the line through the outlet of the first pump on the preceding stroke of the first pump.

Description

~3~

APPARATUS_FOR PUMPING FLUE,NT_SOLID ~TER AL

Backyround of the Invention Thi.s invention relates to apparatus for pumping fluent solid material and more particularly to apparatus for pumping powder.

Summary of the Invention .

Among the several objects of th2 invention may be noted the provision of improved apparatus for pumping fluent solid material, e.g. powder, by means of gas, generally air In general, apparatus of this invention for pumping fluent solid material comprises first and second expansible chamber pumps, the first of which has an inlet with a check valve for intake of material from a supply thereof on an intake stroke arld an outlet with a check valve for discharge of the ma-terial on a discharge stroke through a line or delivery of ma-terial from the outlet, the second of which has an inlet with acheck valve for intake of gas on an intake stroke and an outlet w.ith a check valve for discharge of gas on a discharge stroke jeans interconnects the pumps for operation of the second pump through a discharge stroke on an intake stroke of the first pump and through an intake stroke on a discharge stroke of the first pump. A line interconnects the outlet of the second pump to the material delivery line downstream from and adjacent the outlet of the first pump whereby on each discharge stroke of the first pump the second pump takes in gas and on each intake stroke of 3~

the first pump the second pump pumps gas to the material deliv-ery line behind the material delivered into the line through the outlet of the irst pump on the preceding stroke of the first pump.
Other objects and features will be in part apparent and in par pointed out hereinafter.

grief n~c8~ of the Drawings Fig. 1 is a view of apparatus of the present invention with parts broken away and shown in sections;
Fig. 2 is a view of a check valve used in a pump of the apparatus showing in solid lines a valve member in closed position and in phantom the valve member open;
Fig 3 is an end view of Fig. 2 (as viewed from the top of Fig. 2); and FigO 4 is a view similar to Fig. 2 showing a modification of the check valve.

Corresponding reference characters indicate corre-sponding parts throughout the several views of the drawings.

Description of the Preferred Embodiment Referring to Fig. 1 of the drawings, apparatus of this invention, which is particularly adapted for pumping fluent solid material such as powderi is shown to comprise a dual ex-pansible chamber pump generally designated 1, comprising a first expansible chamber pump 3 and a second expansible chamber pump 5, The first pump has an inlet 7 with a check valve 9 for in-take through a supply line 11 of fluent material (e.g. powder to be pumped from a supply thereof (not shown) on an intake ~3~

stroke of the first pump, and an outlet 13 with a check valve 15 for discharge of the material on a discharge stroke of the firs pump through a deiivery line 17~ The second pump has an inlet 19 with a check valve 21 for intake of gas on an intake stroke of the second pump, and an outlet 23 with a check valve 25 for discharge of gas on a discharge stroke of the second pumpr Gas intake may be air intake from the ambient atmosphere via an air filter 27. jeans indicated at 29 interconnects the pumps for operation of a second pump 5 through a discharge stroke on an intake stroke of the first pup 3 and through an intake stroke on a discharye stroke of the first pump. A line 31 intercon-nects the outlet 23 of the second pump 5 to said material delivery line 17 downstream from and adjacent the outlet 13 of the first pump 3, whereby on each discharge stroke of the first pump 3 the second pump 5 takes in gas (e.g. air) and on each intake stroke of the first pump 3 the second pump 5 pumps gas to said material delivery line 17 behind the material delivered into said line through the outlet of said first pump on the preceding stroke of said first pump. A check valve 33 is pro-vided for the line 31 arranged to close on discharge of materialthrough the outlet 13 into said material delivery line 17 and to open on delivery of gas through the line 31.
ore par~icularly~ the dual pump l is a double-dia-phragm pump, each of pumps 3 and 5 being a diaphragm pump com-prising a housing generally designated 35 and a diaphragm divid-ing the housing into a pump chamber and an operating chamber.
The diaphragm of the first pump 3 (the material pump) is desig-nated 37 and its pump and operating chambers are respectively designated Cl and C2. The diaphragm of the second pump 5 (the gas pump) is designated 39 and its pump and operating chambers 62L~/sd TRC 296 are respectively designated C3 and C4. The pumps are powered by compressed air (or other gas) in conventional manner, an air distributor valve 41 being operable in well-known manner with respect to double-diaphragm pumps alternately to deliver air 5 under pressure to operating chamber C2 of pump 3 while exhaust-ing air from operating chamber C4 of pump 5 so as to operate pump 3 through a pumping stroke and pump 5 through an intake stroke, and to deliver air under pressure to chamber C4 of pump 5 while exhausting air from chamber C2 of pump 3 to operate pump 3 through an intake stroke and pump 5 through a pumping stroke.
Passage 43 interconnects valve 41 and chamber C2 of pump 3 for delivery to and exhaust of air from this chamber and passage 45 interconnects valve 41 and chamber C4 of pump 5 for delivery to and exhaust of air from the latter chamber. the aforesaid con-necting mean9 29 comprises a rod 47 interconnecting the dia-phragms 37 and 3~ so that when one moves to the right as shown in Fig. 1, the other moves to the left, and vice versa.
Check valves 9 and 15 foî the inlet and outlet, re-spectively, of pump 3 are generally identical. jigs. 2 and 3 show the valve (lS being indicated) as comprising an annular raised valve seat 49, a flexible flap 51 carrying a valve member 53 enyageable with the seat, and a raised support 55 for the slap with a spaee 57 below the support. The seat comprises a plate 59 havlng an opening l therein and an annular flange 63 bent up from the materiai ox the plate around the opening. This flange could be a separate attached part. The flange 63 has a relatively thin (e.g. r chamfered) edge 64 engageable by the valve member 53. The slap 51 is of pliable material and has a 62LH/sd TRC 2969 rigid (metal) head 65 or weight secured thereto on the face thereof toward the valve seat. The valve member 53 is an elastomeric member secured on the face of the metal head toward the valve seat and is greater in diameter than the opening 61 to insure full closure oE the opening. It is pxeferably made of a low durometer elastomer resistant to being cut by the flange 63. The raised support 55 comprises upper and lower bars 67 and 69, respectively, extending over bushings 71 and 73 on a pair of bolts 75 and 77 extending from plate 59. Nuts 79 and 81 threaded on the bolts constitute means for clamping the flap 51 between the bars.
At 83 is indicated a relatively short outlet pipe ex-tending from outlet 13 of pump 3. The material delivery line 17 comprises a pipe 85 having a belled end involving a flaring shoulder portion 87 and a ring portion 89 surrounding and sealed to the outlet pipe as by threading at 91. The threading allows for adjustment. A double Oaring and set screw arrangement may be used to permit adjustment. on elastomeric (rubber) sleeve 93 forming a check valve for closing off air line 31 from material discharged into line 17 is fitted on pipe 83 extending off the ' end of the pipe 83 with its free end normally engaging the in-; terior of shoulder portion 89 to seal off a chamber 95 between 83, 93 and 89~ Air line 31 connects to this chamber. The ar-rangement is such that sleeve 93 normally closes off chamber 95 and line 31 prom material delivered through pipe 83 and sleeve 93 but, on delivery of air through line 31 to chamber 95, the sleeve is squeezed to open for flow of the air past the free end of the sleeve into line 17.
Fig. 1 shows diaghragm 37 at the end of its pumping stroke (illustrating valve 9 closed and valve 15 open) and dia-phragm 39 at the end of its intake stroke (illustrating valve 21 open and valve 25 closed). At this point distributor valve 41 ~33~

directs air under pressure through passage 45 into chamber C4 and opens chamber C2 to exhaust. accordingly, as diaphragm 37 moves through an intake stroke and diaphragm 39 moves through a pumping stroke valve 9 opens, valve 15 closes, and a charge of fluent material is suctioned into chamber Cl through supply line 11. Valve 21 closes, valve 25 opens, and air under pressure is delivered through line 31 to the space around the sleeve valve 93, squeezing it for disengagement of its ree end from shoulder 8~, or delivery of a slug of air through line 17 downstream from the vaLve 93 behind the material delivered into line 17 through pump sutlet 13 and pip 83 on the preceding discharge stroke of diaphragm 37 of the pump 3. Then distributor valve 41 reverses, directing air under pressure through passage 43 in-to chamber C2 and opening chamber C4 to exhaust, so that dia-phragm 37 is driven through a pumping stroke and diaphragm 39 is driven through an intake stroke. Valve g closes, valve 15 opens, and the charge of fluent material that had been suctioned into chamber Cl is pumped out through outlet 13, pipe 83, sleeve 93 and pipe 85. A charge of air is taken into chamber C4 for 20 the next pulsing of air into the line 17 behind a slug of mate-rial. The action is repeated, and this effects alternate intake and discharge of fluent material into and out of chamber Cl and air into and out of chamber C3. As will be understood from the above, this motion results in slugs of air being pumped into line 17 between slugs of material.
It will be understood that the two pumps of the appar-atus do not have to be of identical 5ize and volume. For exam-ple, the firs pump 3 could be larger in size and volume thanthe second pump 5 thereby allowing a larger amount of material to be sucked into chamber Cl and pumped into line 17. In order to accomplish this and still maintain the efficiency of the ap-paratus, the connecting rod 47 is modified to allow additional ~;33~

extension of it as it moves into the f irst pump 3. This may be achieved by making thy rod of two telescoping sections with a tension spring therebetween. This, when the air from the dis-tributor valve works against the first diaphragm 37~ pulling the rod into the first pump, a section of the rod can extend against the bias of the spring and force all the fluent material in chamber Cl throush outlet 13. The extended section of the rod will return to it.s normal position when the valve 41 reverses its action.
In addition, the apparatus may further comprise a line 95 connected to line 11 downstream of the source of fluent mate-rial with a valve 97 therein. The lz~ter valve constitut2s means for admitting air to chamber Cl of the first pump 3r with the first pump in operation, for flushing the first pump and the material delivery line 17~ The system is "flushed" by either opening valve 97 for a certain number of strokes or for a set period of time. A control 99 (shown in phantom) may be used to automatically open and close the valve at predetermined inter-Yals. A by-pass line 101 with a valve 103 therein may be u~i-lized continuously to bleed air into line 11 to dilute the pow-der stream for better flow and pumping characteristics.
The apparatus as above described is such as to enable pumping (or conveying) of the powder with less gas (air and at lower gas delivery velocity through the delivery line 17 thereby to permit discharge of the powder from line 17 into an open receiver (not shown) without requiring use of means for separating the powder from the gas stream. The valve shown at 33 eliminates obstructions for the flow of powder and also avoids pocketing of the powder. Leakage i5 avoided by reason of the edge 64 being thin and by reason of the fact that any particle which may remain on the edge generally becomes embedded in the elastomeric valve member. however, a flapper type valve ~:33~
could be used. moreover, any other suitable type of valve, such as a ball check valve, may be utilized in place of the valves shown. Fig. 4 illustrates a modification of the check valve used at 9 and 15 which is similar to that shown in Figs. 2 and 3 in comprising plate 59 having opening 61 therein and annular flange 63 as a separate attached par having relatively thin edge 64 engageable by elastomeric valve member 53. The latter is secured on the face of flap 51 toward the valve seat with the metal head or weight 65 on the other Eace of the flap, the l securement being by means o a screw 95 havi.ng its head 97 engaging the valve member and threaded in a hole in the head 65.
In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous re-suit attained .
- As various changes could be made in the above con-struction without departing from the scope of the invention, it is intended what all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense ., .

Claims

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

l. Apparatus for pumping fluent solid material com-prising:

a first expansible chamber pump having an inlet with a check valve for intake of material from a supply thereof on an intake stroke of said first pump and an outlet with a check valve for discharge of the material on a discharge stroke of said first pump;

a line for delivery of material from the outlet of said first pump;
a second expansible chamber pump having an inlet with a check valve for intake of gas on an intake stroke of said second pump and an outlet with a check valve for discharge of gas on a dis-charge stroke of said second pump;

means interconnecting the pumps for operation of the second pump through a discharge stroke on an intake stroke of the first pump and through an intake stroke on a discharge stroke of the first pump; and a gas line interconnecting the outlet of the second pump to said material delivery line downstream from and adjacent the outlet of the first pump whereby on each discharge stroke of the first pump the second pump takes in gas and on each intake stroke of the first pump the second pump pumps gas to said material deliv-ery line behind the material delivered into said line through the outlet of said first pump on the preceding stroke of said first pump.
2. Apparatus as set forth in claim 1 wherein a check valve is provided for the gas line arranged to close on dis-charge of material through the outlet into said material deliv-ery line and to open on delivery of gas through the gas line.
3. Apparatus as set forth in claim 2 having means for admitting gas to said first pump with said first pump in operation for flushing said first pump and said material deliv-ery line.
4. Apparatus as set forth in claim 3 having a mate-rial supply line for delivery of material from the supply to the inlet of the first pump and a valved gas intake for said supply line.
5. Apparatus as set forth in claim 2 wherein each check valve in the first pump comprises means providing an annu-lar raised valve seat, a flexible flap carrying a valve member engageable with the seat, and a raised support for the flap with a space below the support.
6. Apparatus as set forth in claim 5 wherein the means providing the seat comprises a plate having an opening therein and an annular flange extending up around the opening, said flange having a relatively thin edge engageable by the valve member, the flap being of pliable material, having a rigid head secured thereto, the valve member being an elastomeric.
7. Apparatus as set forth in claim 2 wherein the check valve for the gas line comprises an elastomeric sleeve through which material is delivered from said first pump, a gas chamber surrounding the sleeve to which gas is delivered by the gas line, the sleeve having a free end engaging a shoulder in the material delivery line.
8. Apparatus as set forth in claim 1 wherein each pump is a diaphragm pump and the means interconnecting the pumps comprises a rod interconnecting the diaphragms of the pumps.
9. Apparatus as set forth in claim 8 wherein a check valve is provided for the gas line arranged to close on discharge of material through the outlet into said material delivery line and to open on delivery of gas through the gas line.
10. Apparatus as set forth in claim 9 having means for admitting gas to said first pump with said first pump in operation for flushing said first pump and for diluting material entering said first pump.
11. Apparatus as set forth in claim 10 having a mate-rial supply line for delivery of material from the supply to the inlet of he first pump and a valved gas intake for said supply line.
12. Apparatus as set forth in claim 9 wherein each check valve in the first pump comprises means providing an annu-lar raised valve seat, a flexible flap carrying a valve member engageable with the seat, and a raised support for the flap with a space below the support.
13. Apparatus as set forth in claim 12 wherein the means providing the seat comprises a plate having an opening therein and an annular flange extending up from the plate around the opening, said flange having a relatively thin edge engageable by the valve member, the flap being of relatively thin, pliable material, having a rigid head secured thereto, the valve member being an elastomeric member.
14. Apparatus as set forth in claim 9 wherein the check valve for the gas line comprises an elastomeric sleeve through which material is delivered from said first pump, a gas chamber surrounding the sleeve to which gas is delivered by the gas line, the sleeve having a free end engaging a shoulder in the material delivery line.